1. Field of the Invention
The present invention relates to a power supply apparatus and a power supply system, and particularly to a power supply apparatus and a power supply system that address an output abnormality or the like of the power supply apparatus.
2. Description of the Background Art
A power supply system detecting an output abnormality of a power supply apparatus and managing the power supply apparatus has been developed. For example, Japanese Patent Laying-Open No. 2004-227555 (Patent Document 1) discloses a power supply management and control apparatus for a power supply device as described below. This apparatus manages and controls electric current supplied to a plurality of loads in a load system of the power supply device. The apparatus includes a switch device including a plurality of current paths and supplying an output voltage supplied from the power supply device through different current paths to different loads respectively, a microcontroller controlling an open/close status of the switch device, a set reference value storage unit linked to the microcontroller and storing a rated total output current value of the power supply device as set in advance, and a priority sequence storage unit linked to the microcontroller and storing the number of loads in the whole system and an operational item of a sequence of priority of shutting down the loads as determined in advance. When the microcontroller detects that the actual total output current exceeds the rated total output current value as set of the power supply device, current supply to at least one load is shut down according to the sequence of priority of shutting the loads. When the actual total output current is smaller than the rated total output current value, loads for which the current supply is previously shut down are restarted according to the opposite sequence of priority of shutting down the loads.
However, the power supply management and control apparatus for the power supply device disclosed in Patent Document 1 monitors the output current of the power supply device by the microcontroller to control the power supply device, and thus the line connecting the microcontroller and the power supply device is complicated. Further, it is necessary that the microcontroller includes a terminal for receiving the output current of the power supply device and a circuit for measuring the output current value. Therefore, the power management and control apparatus for the power supply device disclosed in Patent Document 1 has a problem of the complicated circuit configuration.